Referees resume with EB1- A and NIW applications

[SunJune]

Should the referees resume be submitted with EB1-A or NIW applications?

I understand that it may be necessary to submit resumes with EB1-A to corroborate the referees background, but is it the same with NIW petitions as well?

Essentially, are these required by the USCIS? What is the best practice that one can follow?

Thanks